Paleoicnologia de Crocodylomorpha e sua ocorrência na Bacia Rio do Peixe (Cretáceo Inferior), Nordeste do Brasil

Abstract

The Tapera ichnosite, located in the Rio do Peixe Basin (Paraíba, Brazil), preserves a unique suite of vertebrate trace fossils within fluvio-palustrine deposits of the Barremian–Hauterivian Sousa Formation. This sedimentary unit, developed under semi-arid climatic conditions with episodic waterlogging and cohesive substrates, provides ideal conditions for exceptional soft-sediment preservation. Through high-resolution 3D modeling and sedimentological analysis, we re-evaluate crocodylomorph traces previously documented at the site, expanding the ichnological dataset and refining behavioral interpretations. The trackways include deep ventral impressions and rhythmic lateral sediment disruption, occasionally accompanied by pes and manus prints, and are interpreted as records of large-bodied crocodyliforms using low-walking and belly-sliding locomotion across a gently inclined, water-saturated substrate. The ichnological features closely align with the ichnogenus Crocodylopodus, though the Tapera traces notably exceed its known size range and present unusually prominent ventral morphology. These findings contribute to the understanding of vertebrate-substrate interaction in continental rift basin environments and provide new data for the paleoenvironmental and paleobiogeographic reconstruction of the Early Cretaceous in central Gondwana.